• BMB Reports
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• v.39 no.6
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• pp.743-748
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• 2006

The complement (C) regulatory proteins decay accelerating factor (DAF, CD55) and CD59 could protect host cells using different mechanisms from C-mediated damage at two distinct levels within the C pathway. Co-expression of DAF and CD59 would be an effective strategy to help overcome host C-induced xenograft hyperacute rejection. In this study, we made a construct of recombinant expression vector containing DAF and CD59 cDNA and the stable cell lines were obtained by G418 selection. Extraneous genes integration and co-expression were identified by PCR, RT-PCR and Western blot analysis. Human c-mediated cytolysis assays showed that NIH/3T3 cells transfected stably with pcDNA3-CD59, pcDNA3-DAF, and pcDNA3-CD59DAF-DP were protected from C-mediated damage and that synchronously expressed human CD59 and DAF provided the most excellent protection for host cells as compared with either human CD59 or DAF expressed alone. Therefore, the construct represents an effective and efficacy strategy to overcome C-mediated damage in cells and, ultimately, in animals.

• BMB Reports
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• v.45 no.7
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• pp.408-413
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• 2012

Almost all melanoma cells express at least one member of the MAGE-A antigen family, making the cytotoxic T cells (CTLs) epitopes with cross-immunizing potential in this family attractive candidates for the broad spectrum of anti-melanoma immunotherapy. In this study, four highly homologous peptides (P264: FLWGPRALA, P264I9: FLWGPRALI, P264V9: FLWGPRALV, and P264H8: FLWGPRAHA) from the MAGE-A antigens were selected by homologous alignment. All four peptides showed high binding affinity and stability to HLA-A$^*02:01$ molecules, and could prime CTL immune responses in human PBMCs and in HLA-A$^*02:01/K^b$ transgenic mice. CTLs elicited by the four epitope peptides could cross-lyse tumor cells expressing the mutual target antigens, except MAGE-A11 which was not tested. However, CTLs induced by P264V9 and P264I9 showed the strongest target cell lysis capabilities, suggesting both peptides may represent the common CTL epitopes shared by the eight MAGE-A antigens, which could induce more potent and broad-spectrum antitumor responses in immunotherapy.

• Journal of Microbiology and Biotechnology
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• v.14 no.4
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• pp.730-736
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• 2004

This study aims at characterizing the bacteriophages isolated from activated sludge performing enhanced biological phosphorous removal (EBPR) to understand the interactions between the phage-host system and bacterial community. Sixteen bacterial isolates (E1-E16) were isolated as host bacterial strains from EBPR activated sludge for phage isolation. Forty bacteriophages based on their plaque sizes (2 plaques on E4, 4 on E8, 11 on E10, 5 on E14, 18 on E16) were obtained from filtered supernatant of the EBPR activated sludge. Each bacteriophage did not make any plaque on bacterial strains tested in this study except on its own host bacterial strain, respectively, indicating that the bacteriophages are with narrow host specificity. However, fourteen of the forty bacteriophages obtained in this study lost their virulent ability even on their own host bacteria. All of the lytic phages showed similar one-step growth patterns and had long latent period (about 9 hours) to reproduce their phage particles in their host bacterial cells. On the other hand, their probable burst sizes (6 to 48 per host cell) were large enough to actively lyse their host bacterial cells. Therefore, it could be implied that bacteriophages are also important members of the microbial community in EBPR activated sludge, and lytic phages directly decrease the population size of their host bacterial groups in EBPR activated sludge by lysis.

• Journal of Korean Society of Water and Wastewater
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• v.29 no.2
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• pp.203-209
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• 2015

The purpose of this study is to estimate the applicability of a stable anaerobic digester using a separator membrane to the preprocessing thickening process. The results of the experiments showed about a 47.16% weight loss rate for the sludge under anaerobic condition, and about 41.17% under intermittent aeration condition. The concentrations of rejection water were $SCOD_{Cr}$ 25 mg/L, T-N 16.6 mg/L, and T-P 1.4 mg/L on the average under the intermittent aeration condition, which were lower than the concentrations of rejection water under an anaerobic condition. As for the factors affecting the reduction of the flux, correlation analyses of TTF, MLSS, $SCOD_{Cr}$, and $EPS_{Protein}$, $EPS_{Polysacchride}$ resulted in -0.97, -0.95, -0.84 and -0.86, -0.95, respectively, which showed that TTF had the highest correlation to the reduction of the flux. In addition, it was concluded that MLSS, $SCOD_{Cr}$ and $EPS_{Protein}$, $EPS_{Polysacchride}$ also have close correlations. The results are considered to show that, in the case of the process using a tubular membrane in the preprocessing process of an anaerobic digester, an intermittent aeration condition of the thickener considering the contamination of the membrane and load of rejection water is appropriate for the stable preprocessing process.

• Korean Journal of Microbiology
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• v.51 no.2
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• pp.108-114
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• 2015

We tried to analyze the growth time for secretion of the iron containing superoxide dismutase by comparing the intra-and extracellular enzyme activity from Streptomyces subrutilus P5 and analyze possible genetic information for this enzyme secretion. The mycelial dry weights and glucose concentrations in culture filtrates were determined during growth. Glucose was consumed rapidly during logarithmic growth phase and almost exhausted at 24 h of cultivation. While the intracellular activity of iron containing superoxide dismutase was first appeared at three hours, the extracellular activity of this enzyme appeared from 7.5 h of cultivation, early logarithmic growth phase. This early presence of the superoxide dismutase might not be the result of cell lysis but active secretion pathway. There was no information for signal peptide responsible for the enzyme secretion in sodF. However, we found a type three secretion box in the promoter region of sodF that has been known for the genes of type III secreted proteins in other bacteria. This is the first report on the possible existence of type III secretion in Streptomyces.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.98-105
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• 2014

Lysozyme amounts to 0.3% in egg white and functions as an agent of cell lysis and activator of tissue reconstruction. Ion exchange chromatography is the most useful method of separation among affinity chromatography, ion exchange chromatography, and ultra-filtration. The aim of present study is to find the optimum pH and temperature for the separation of lysozyme in egg white within cation exchange gel filled glass column. And we compared results of experiments with those of simulations. Phosphate buffer was used, and pH and temperature were varied as 5~7 and $25{\sim}40^{\circ}C$ respectively. RP-HPLC was the tool for the retention time identification and quantitative analysis of lysozyme. OriginPro 8 measured the peak area of lysozyme chromatogram and quantified the eluted lysozyme. Largest amount of lysozyme was separated under the conditions of pH 5 and T $25^{\circ}C$.

• Korean Journal of Microbiology
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• v.27 no.1
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• pp.56-62
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• 1989

Antagonistic effects of Streptomyces species aganinst Fusarium solani causing ginseng root rot were investigated in terms of chitinase activity and growth inhibition in vitro. Among 131 isolates of streptomycetes obtained from ginseng cultivating soil, 9 isolates producing large clear zone around the colony on a chitin agar medium were selected for further study. All 9 isolates produced chitinase in a range from 0.10 to 0.38 U lysing cells of F. solani and inhibited germination of the conidia. In the ten-fold condentrated culture filtrate of S. alboniger ST59 and S. roseolilacinus ST129, the number of conidia of F. solane was reduced to about 20% of original count within 14 days. When S. alboniger ST59 and F. solani were grown simultaneously in the mineral saly medium, chitinase activity increased with incubation period, whereas mycelial volume of F. solani decreased. In a chitin added mineral salt medium, chitinase activity increased during the first four days and maintained steady level until the 8th day, and increased thereafter. S. alboniger ST59 lysed mycelia, conidia and even chlamydospores of F. solani. It is probable that the antagonistic activity of this streptomycete against F. solani is the lysis of fungal cell wall by streptomycete producing chitinase affected by antifungal substances.

• Korean Journal of Microbiology
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• v.33 no.3
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• pp.170-174
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• 1997

In order to design a novel synthetic peptide with improved fungicidal activity but low hemolytic activity, a hybrid peptide, cecropin A(l-8)-magainin 2(1-12), and its analogue peptides were synthesized by the solid phase method. Antifungal and hemolytic activities of the synthetic peptides were assessed by the growth inhibition against Trichosporon beigelii and the cell membrane lysis against human red hlood cells, respectively. Analogue 2 in which Lys at position 12 in cecropin A(1-8)-magainin 2(1-12) was substituted with Ala showed most potent antifungal activity (MIC: 2.5.$\mu$g/ml) with minimal hemolytic activity (0.5% hemolysis at the (200.$\mu$g/ml peptide). This peptide (A2), therefore, could be useful as a model for further designing potent antifungal peptides without cytotoxicity.

• Journal of Fisheries and Marine Sciences Education
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• v.28 no.6
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• pp.1662-1672
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• 2016

To address physicochemical factors of yellow clay for removing Cochlodinium polykrikoides blooms, the correlation of removal efficiency with mineralogical characteristics of yellow clay collected from various areas was surveyed. Yellow clay from different localities showed the wide range of chemical compositions $SiO_2$ : 43~71%, $Al_2O_3$ : 13~26%, $Fe_2O_3$ : 5~14%, MgO : 0.4~1.8%, $K_2O$ : 0.6~3.3%, L.O.I.(Loss of Ignition) : 4.5~15%. The mineral compositions of yellow clay were mainly consisted of quartz and feldspar including small amounts of kaolinite, chlorite, and Fe-oxides. The result of size analysis showed that $6{\Phi}(31{\sim}16{\mu}m)$ and $7{\Phi}(16{\sim}8{\mu}m)$ were dominated sizes. The zeta-potential were in the range of -4.1~-20.7mV(average -13.7). As increasing removal efficiency of C. polykrikoides, contents of $Al_2O_3$, $Fe_2O_3$ and L.O.I. in yellow clay increased, whereas $SiO_2$ content decreased. Furthermore, the amounts of silt mineral and small particle were high when the removal efficiency was high. According to factor analysis using principle component analysis, two components of factor 1 and factor 2 showed 79% of the total variance, which is related to cohesion and adsorption. Inducing cell lysis of C. polykrikoides by cohension and adsorption between C. polykrikoides and yellow clay.

• Journal of Ginseng Research
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• v.29 no.4
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• pp.176-181
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• 2005

Our previous reports demonstrated that ip. administration of Korean red ginseng acidic polysaccharide (RGAP) exerts antitumor activity In mice. The present study was carried out to compare the effects of ip. and p.o. routes of administration of RGAP on either normal or tumor-bearing BALB/c mice. RGAP was administered either ip. or p.o. at doses of 100, 300, 500, 1000 mg/kg for 1 or 5 weeks. Peritoneal macrophages from mice treated with RGAP p.o. at a dose of 300 mg/kg either for 1 or 5 weeks did not exhibit growth inhibition activity toward WEHI-I64 tumor cells. However, administration of RGAP at a dose of 600 mg/kg for both 1 and 5 weeks increased the antitumor activity of macrophages. Oral administration of RGAP (600 mg/kg) for 5 weeks and ip. administration of RGAP (300 mg/kg) for 1 week resulted in antitumor activities of $40\%$ and $45\%$, respectively, indicating that the effect of i.p. injection is more potent 2 and 5 times than that of p.o. one in terms of dose and duration, respectively. Tumor inhibition rates of RGAP at doses of 300, 500, 1000 mg/kg in mice transplanted with B16-F10 melanoma were 4.4, 12.0, and $45.4\%$, respectively, meaning that p.o. dose higher than 500 mg/kg possess marked antitumor activity. The results above suggests that p.o. administration of RGAP also show antitumor activity in vivo depending on the dose.